Delinquent Taxes in Northern VA

Now that I have a list, what should I do with it. I've removed low amounts owed, I am ready to calculate the property values, determine where things stand once I see value, taxes owed, and loans owed. Anything else I should do to organize my list?

If someone owes half of the value of their home in taxes what should I do? If the home is paid off with 3 years of taxes owed, how should I approach them? Who should I market to for the investor in me vs. the Realtor in me? Whatever tips, tricks, articles, YouTube Videos, etc you can offer please share :-)

If you are a Tax Delinquent Jedi, please connect with me!